1. Field
This disclosure relates to a solution composition, and a method of forming a thin film and a method of manufacturing a thin film transistor using the solution composition.
2. Description of the Related Art
A thin film transistor (TFT) is used in various fields, and it is particularly used for a switching and driving device in a flat panel display such as a liquid crystal display (LCD), an organic light emitting diode display (OLED display), and an electrophoretic display (EPD).
The thin film transistor generally includes a gate electrode connected to a gate line transferring a scan signal, a source electrode connected to a data line transferring a signal applied to a pixel electrode, a drain electrode facing the source electrode, and a semiconductor electrically connected to the source electrode and the drain electrode when a predetermined voltage is applied.
The semiconductor is one of primary components for determining the characteristics of a thin film transistor. Such a semiconductor is generally composed of silicon (Si). Silicon is classified into amorphous silicon and polycrystalline silicon depending upon the crystal shape. Amorphous silicon may be obtained by a simple manufacturing process, but has insufficient charge mobility to provide a high performance thin film transistor, while polycrystalline silicon has high charge mobility, but it requires a step of crystallizing silicon which increases the cost and complicates the process.
Instead of the amorphous silicon and the polycrystalline silicon, an oxide semiconductor may be used. The oxide semiconductor may increase the charge mobility depending upon the deposition conditions when it is formed by vacuum deposition, and it does not require the additional process for crystallizing the semiconductor. However, since the vacuum deposition is a complicated process, it incurs a high cost, and it is limited in application to a large display device.